Conventionally, for example, Patent Literature 1 describes a power storage device in which two each, four in total, of laminated batteries as unit batteries are attached to each of both surfaces of a substantially flat-plate battery housing body using a two-sided tape or the like so as to construct a battery module, and a plurality of such battery modules is housed in a housing in a state in which they are erected side by side along the longitudinal direction. In particular, referring to FIGS. 2 and 3 of Patent Literature 1, grip section (236) including grip through-hole (235) is provided protruding at one end portion of the battery housing body having a substantially rectangular shape in a plan view, and first and second connectors (232 and 234) are attached to both sides of the grip section.